/* =============================================================================
   Agentic QE Explainer — FORGE / FLEET
   Aesthetic: deep warm-charcoal substrate, amber/copper accents, industrial
   display type, generous space. Adapted from Ruv-Explainer design system.
   ========================================================================== */

/* ---- Google Fonts (CDN) --------------------------------------------------- */
@import url('https://fonts.googleapis.com/css2?family=Big+Shoulders+Display:wght@600;900&family=IBM+Plex+Mono:wght@400&family=IBM+Plex+Sans:wght@400;500&display=swap');

/* ---- :root DESIGN TOKENS ------------------------------------------------- */
:root {
  --bg:          #16120e;
  --bg-2:        #1d1812;
  --panel:       #241d15;
  --panel-2:     #2c2418;
  --ridge:       #3a2f1f;

  --amber:       #ff9e2c;
  --amber-hot:   #ffb650;
  --copper:      #c2703a;
  --copper-deep: #8a4a26;
  --ember:       #e8531f;
  --brass:       #d9a441;

  --ink:         #f3e8d8;
  --ink-2:       #d6c5ac;
  --muted:       #9c8b72;
  --faint:       #6b5e49;
  --on-amber:    #1a1206;

  --line:        rgba(217,164,65,0.14);
  --line-strong: rgba(217,164,65,0.30);
  --fill-amber:  rgba(255,158,44,0.10);
  --fill-copper: rgba(194,112,58,0.12);

  --shadow:      0 22px 48px -26px rgba(0,0,0,0.82);
  --shadow-deep: 0 38px 90px -40px rgba(0,0,0,0.9);
  --emboss:      inset 0 1px 0 rgba(255,196,120,0.07),
                 inset 0 -1px 0 rgba(0,0,0,0.45);
  --glow-amber:  0 0 0 1px rgba(255,158,44,0.25),
                 0 14px 40px -16px rgba(255,158,44,0.32);

  --display: "Big Shoulders Display", "Arial Narrow", system-ui, sans-serif;
  --sans:    "IBM Plex Sans", system-ui, -apple-system, sans-serif;
  --mono:    "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;

  --maxw:    1120px;
  --gutter:  clamp(20px, 5vw, 56px);
  --radius:  14px;
  --radius-s: 9px;
  --ease:    cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* ---- Reset / base --------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  background-image:
    radial-gradient(1100px 620px at 78% -8%, rgba(255,158,44,0.10), transparent 60%),
    radial-gradient(900px 700px at -10% 8%, rgba(194,112,58,0.08), transparent 55%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
  background-attachment: fixed;
}

img { max-width: 100%; height: auto; display: block; }

a {
  color: var(--amber);
  text-decoration: none;
  transition: color 0.18s var(--ease);
}
a:hover { color: var(--amber-hot); }
a:focus-visible,
summary:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---- Layout --------------------------------------------------------------- */
.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 var(--gutter); }

/* ---- Type system ---------------------------------------------------------- */
h1, h2, h3, h4 {
  font-family: var(--display);
  font-weight: 900;
  line-height: 0.98;
  letter-spacing: 0.005em;
  margin: 0 0 0.5em;
  text-transform: uppercase;
}
h1 { font-size: clamp(2.8rem, 8vw, 5.6rem); }
h2 { font-size: clamp(1.9rem, 4.4vw, 3rem); }
h3 { font-size: 1.5rem; font-weight: 600; letter-spacing: 0.01em; }
p  { margin: 0 0 1rem; max-width: 68ch; color: var(--ink-2); }

.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.36em;
  text-transform: uppercase;
  color: var(--brass);
  font-weight: 400;
  margin: 0 0 14px;
}
.mono { font-family: var(--mono); }
.lede { font-size: 1.18rem; color: var(--ink); max-width: 64ch; }

ol, ul { margin: 0 0 1rem; padding-left: 1.4em; max-width: 68ch; color: var(--ink-2); }
li { margin: 0 0 0.55em; }
li::marker { color: var(--copper); }
li strong { color: var(--ink); }

pre.code-block {
  font-family: var(--mono);
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--amber-hot);
  background: var(--bg);
  border: 1px solid var(--line-strong);
  border-left: 3px solid var(--copper);
  border-radius: var(--radius-s);
  padding: 16px 18px;
  margin: 0 0 1rem;
  overflow-x: auto;
  box-shadow: var(--emboss);
  max-width: 68ch;
}
pre.code-block code {
  background: none; border: none; box-shadow: none; padding: 0;
  font-size: inherit; color: inherit; white-space: pre;
}

code, .cmd {
  font-family: var(--mono);
  font-size: 0.86em;
  color: var(--amber-hot);
  background: var(--fill-amber);
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  padding: 0.12em 0.45em;
  box-shadow: var(--emboss);
}

/* ---- Source repo banner --------------------------------------------------- */
.repo-banner {
  background: linear-gradient(96deg, var(--fill-amber) 0%, var(--panel) 100%);
  border: 2px solid var(--amber);
  border-radius: var(--radius);
  padding: 18px 24px;
  margin: 0 0 28px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  box-shadow: var(--glow-amber), var(--emboss);
}
.repo-banner-icon {
  font-size: 1.6rem;
  flex: 0 0 auto;
}
.repo-banner-text {
  flex: 1 1 auto;
  min-width: 0;
}
.repo-banner-text p { margin: 0; color: var(--ink); }
.repo-banner-text .repo-url {
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--brass);
  word-break: break-all;
}
.repo-banner-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: linear-gradient(96deg, var(--amber-hot), var(--copper));
  color: var(--on-amber);
  font-family: var(--display);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  border-radius: 8px;
  box-shadow: var(--glow-amber);
  transition: transform 0.16s var(--ease), filter 0.16s var(--ease);
  flex: 0 0 auto;
}
.repo-banner-cta:hover {
  transform: translateY(-2px);
  filter: brightness(1.07);
  color: var(--on-amber);
}

/* ---- Provenance / attribution banner -------------------------------------- */
.prov-banner {
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(44,36,24,0.55), rgba(29,24,18,0.45));
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.prov-banner-inner {
  display: flex; flex-wrap: wrap; align-items: center;
  justify-content: space-between; gap: 10px 26px;
  padding-top: 9px; padding-bottom: 9px;
}
.prov-attr {
  margin: 0; max-width: none;
  font-family: var(--sans); font-size: 12.5px; line-height: 1.5;
  color: var(--muted); letter-spacing: 0.01em;
}
.prov-attr strong { color: var(--ink-2); font-weight: 500; }
.prov-attr a { color: var(--brass); }
.prov-attr a:hover { color: var(--amber-hot); }
.prov-live {
  margin: 0; flex: 0 0 auto;
  font-family: var(--mono); font-size: 11.5px; letter-spacing: 0.05em;
  color: var(--faint); white-space: nowrap;
  display: inline-flex; align-items: center; gap: 8px;
}
.prov-live code {
  font-size: 0.95em; color: var(--brass);
  background: var(--fill-amber); padding: 0.08em 0.4em;
}
.prov-dot {
  color: var(--amber); font-size: 9px;
  filter: drop-shadow(0 0 4px rgba(255,158,44,0.8));
  animation: prov-pulse 2.6s var(--ease) infinite;
}
@keyframes prov-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.35; }
}

/* ---- Header / nav --------------------------------------------------------- */
.site-head {
  position: sticky; top: 0; z-index: 40;
  background: rgba(22,18,14,0.78);
  backdrop-filter: blur(11px);
  -webkit-backdrop-filter: blur(11px);
  border-bottom: 1px solid var(--line);
}
.site-head .wrap {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand {
  display: inline-flex; align-items: center; gap: 12px;
  font-family: var(--display); font-weight: 900; font-size: 1.25rem;
  letter-spacing: 0.04em; text-transform: uppercase; color: var(--ink);
}
.brand .coin {
  width: 30px; height: 30px; border-radius: 50%;
  display: grid; place-items: center;
  font-family: var(--display); font-weight: 900; font-size: 13px;
  color: var(--on-amber);
  background: radial-gradient(circle at 34% 28%, var(--amber-hot), var(--copper) 78%, var(--copper-deep));
  box-shadow: var(--glow-amber), var(--emboss);
}
.nav-links { display: flex; gap: 4px; }
.nav-links a {
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.05em;
  color: var(--muted); padding: 7px 11px; border-radius: 7px;
  transition: color 0.18s var(--ease), background 0.18s var(--ease);
}
.nav-links a:hover { color: var(--ink); background: var(--fill-amber); }

/* ---- Hero ----------------------------------------------------------------- */
.hero { padding: clamp(64px, 12vw, 132px) 0 clamp(48px, 8vw, 88px); }
.hero h1 { color: var(--ink); }
.hero h1 .molten {
  background: linear-gradient(96deg, var(--amber-hot), var(--copper) 60%, var(--ember));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero .lede { margin-top: 20px; }
.hero .meta-row {
  display: flex; gap: 26px; flex-wrap: wrap; margin-top: 34px;
  font-family: var(--mono); font-size: 12px; color: var(--faint);
  letter-spacing: 0.05em;
}
.hero .meta-row b { color: var(--brass); font-weight: 400; }
.cta {
  display: inline-flex; align-items: center; gap: 10px; margin-top: 34px;
  font-family: var(--display); font-weight: 600; font-size: 1.05rem;
  letter-spacing: 0.03em; text-transform: uppercase;
  color: var(--on-amber);
  background: linear-gradient(96deg, var(--amber-hot), var(--copper));
  padding: 13px 26px; border-radius: 10px;
  box-shadow: var(--glow-amber), var(--emboss);
  transition: transform 0.16s var(--ease), filter 0.16s var(--ease);
}
.cta:hover { transform: translateY(-2px); filter: brightness(1.06); color: var(--on-amber); }

.hero-inner {
  display: flex;
  align-items: center;
  gap: clamp(32px, 5vw, 72px);
  flex-wrap: wrap;
}
.hero-copy { flex: 1 1 320px; min-width: 0; }
@media (max-width: 700px) {
  .hero-inner { flex-direction: column; }
}

/* ---- Sections (native <details>) ----------------------------------------- */
.sections { padding: clamp(32px, 6vw, 64px) 0 clamp(64px, 10vw, 110px); }

.section {
  background:
    linear-gradient(180deg, var(--panel) 0%, var(--bg-2) 100%);
  border: 1px solid var(--ridge);
  border-radius: var(--radius);
  box-shadow: var(--shadow), var(--emboss);
  margin: 0 0 18px;
  overflow: hidden;
}
.section[open] { box-shadow: var(--shadow-deep), var(--emboss); }

.section > summary {
  list-style: none; cursor: pointer;
  display: flex; align-items: baseline; gap: 18px;
  padding: 26px clamp(20px, 4vw, 34px);
  user-select: none;
  transition: background 0.2s var(--ease);
}
.section > summary::-webkit-details-marker { display: none; }
.section > summary:hover { background: var(--fill-amber); }

.section .num {
  font-family: var(--mono); font-size: 13px; letter-spacing: 0.22em;
  color: var(--copper); flex: 0 0 auto; padding-top: 6px;
}
.section .head-text { flex: 1 1 auto; }
.section .head-text h2 {
  margin: 0; color: var(--ink);
  font-size: clamp(1.4rem, 3.2vw, 2.05rem);
}
.section .head-text .q {
  display: block; font-family: var(--mono); font-size: 12px;
  letter-spacing: 0.06em; color: var(--muted); margin-top: 6px;
  text-transform: none;
}
.section .chev {
  flex: 0 0 auto; width: 26px; height: 26px; align-self: center;
  border-radius: 50%; display: grid; place-items: center;
  border: 1px solid var(--line-strong); color: var(--amber);
  font-size: 13px; line-height: 1;
  transition: transform 0.25s var(--ease), background 0.2s var(--ease);
}
.section[open] .chev { transform: rotate(90deg); background: var(--fill-amber); }

.section .body {
  padding: 4px clamp(20px, 4vw, 34px) 32px;
  border-top: 1px solid var(--line);
  margin-top: 2px;
}
.section .body > *:first-child { margin-top: 18px; }

/* Figure slot */
.figure {
  margin: 24px 0; border: 1px solid var(--ridge); border-radius: var(--radius-s);
  background: var(--panel-2); padding: 18px; box-shadow: var(--emboss);
}
.figure figcaption {
  margin-top: 12px; color: var(--muted);
  font-family: var(--mono); font-size: 12px; letter-spacing: 0.03em;
}
.figure.diagram { background: var(--bg); }
.figure.diagram > svg {
  display: block; width: 100%; height: auto; max-width: 100%;
  border-radius: 6px;
}

/* Grid cards */
.grid {
  display: grid; gap: 16px;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  margin-top: 18px;
}
.card {
  background: var(--panel-2); border: 1px solid var(--ridge);
  border-radius: var(--radius-s); padding: 20px; box-shadow: var(--emboss);
}
.card .tag {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.16em;
  text-transform: uppercase; color: var(--copper);
}
.card h3 { margin: 8px 0 10px; color: var(--ink); }

/* Agent table */
.agent-table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0;
  font-size: 0.92rem;
}
.agent-table th {
  text-align: left;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--copper);
  padding: 10px 14px;
  border-bottom: 2px solid var(--ridge);
}
.agent-table td {
  padding: 10px 14px;
  border-bottom: 1px solid var(--line);
  color: var(--ink-2);
  vertical-align: top;
}
.agent-table td:first-child {
  color: var(--ink);
  font-weight: 500;
}
.agent-table tr:hover td {
  background: var(--fill-amber);
}

/* Platform badges */
.platform-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 14px 0;
}
.platform-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--panel-2);
  border: 1px solid var(--ridge);
  border-radius: 20px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--ink-2);
}
.platform-badge.active {
  border-color: var(--amber);
  color: var(--amber);
}

/* ---- Get started section -------------------------------------------------- */
.install-block {
  margin: 18px 0;
  padding: 20px 24px;
  border: 2px solid var(--amber);
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--fill-amber) 0%, var(--panel) 100%);
  box-shadow: var(--glow-amber), var(--emboss);
}

/* ---- Dropzone ------------------------------------------------------------- */
.dropzone {
  margin-top: 22px; border: 2px dashed var(--copper-deep);
  border-radius: var(--radius); padding: clamp(28px, 6vw, 52px);
  text-align: center; background: var(--fill-copper);
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease),
              transform 0.2s var(--ease);
  cursor: pointer;
  display: block;
}
.dropzone:hover { border-color: var(--copper); background: var(--fill-amber); color: var(--ink); }
.dropzone .dz-icon {
  font-family: var(--display); font-weight: 900; font-size: 2rem;
  color: var(--amber); margin-bottom: 8px;
}
.dropzone .dz-hint {
  font-family: var(--mono); font-size: 12px; color: var(--muted);
  letter-spacing: 0.04em; margin-top: 10px;
}

/* ---- Footer --------------------------------------------------------------- */
footer {
  border-top: 1px solid var(--line);
  padding: 48px 0 72px;
  color: var(--faint);
  font-family: var(--mono); font-size: 12.5px; letter-spacing: 0.03em;
}
footer a { color: var(--brass); }
footer .prov { margin-top: 10px; color: var(--muted); }
footer .builder-credit {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--faint);
}

.stack-links {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: 8px 22px;
  margin-bottom: 16px; padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}
.stack-links .stack-lead {
  color: var(--faint); text-transform: uppercase; letter-spacing: 0.12em;
}
.stack-links a { color: var(--brass); }
.stack-links a:hover { color: var(--amber-hot); }

/* ---- Responsive ----------------------------------------------------------- */
@media (max-width: 640px) {
  body { font-size: 16px; }
  .nav-links { display: none; }
  .section > summary { gap: 12px; padding: 20px 18px; }
  .section .num { padding-top: 4px; }
  .hero .meta-row { gap: 16px; }
  .repo-banner { flex-direction: column; align-items: flex-start; }
}

/* ---- Reduced motion ------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .cta:hover { transform: none; }
}